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  <div class="section" id="module-types">
<span id="types-dynamic-type-creation-and-names-for-built-in-types"></span><h1><a class="reference internal" href="#module-types" title="types: Names for built-in types."><code class="xref py py-mod docutils literal notranslate"><span class="pre">types</span></code></a> --- Dynamic type creation and names for built-in types<a class="headerlink" href="#module-types" title="永久链接至标题">¶</a></h1>
<p><strong>Source code:</strong> <a class="reference external" href="https://github.com/python/cpython/tree/3.7/Lib/types.py">Lib/types.py</a></p>
<hr class="docutils" />
<p>This module defines utility functions to assist in dynamic creation of
new types.</p>
<p>It also defines names for some object types that are used by the standard
Python interpreter, but not exposed as builtins like <a class="reference internal" href="functions.html#int" title="int"><code class="xref py py-class docutils literal notranslate"><span class="pre">int</span></code></a> or
<a class="reference internal" href="stdtypes.html#str" title="str"><code class="xref py py-class docutils literal notranslate"><span class="pre">str</span></code></a> are.</p>
<p>Finally, it provides some additional type-related utility classes and functions
that are not fundamental enough to be builtins.</p>
<div class="section" id="dynamic-type-creation">
<h2>Dynamic Type Creation<a class="headerlink" href="#dynamic-type-creation" title="永久链接至标题">¶</a></h2>
<dl class="function">
<dt id="types.new_class">
<code class="descclassname">types.</code><code class="descname">new_class</code><span class="sig-paren">(</span><em>name</em>, <em>bases=()</em>, <em>kwds=None</em>, <em>exec_body=None</em><span class="sig-paren">)</span><a class="headerlink" href="#types.new_class" title="永久链接至目标">¶</a></dt>
<dd><p>Creates a class object dynamically using the appropriate metaclass.</p>
<p>The first three arguments are the components that make up a class
definition header: the class name, the base classes (in order), the
keyword arguments (such as <code class="docutils literal notranslate"><span class="pre">metaclass</span></code>).</p>
<p>The <em>exec_body</em> argument is a callback that is used to populate the
freshly created class namespace. It should accept the class namespace
as its sole argument and update the namespace directly with the class
contents. If no callback is provided, it has the same effect as passing
in <code class="docutils literal notranslate"><span class="pre">lambda</span> <span class="pre">ns:</span> <span class="pre">ns</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified">3.3 新版功能.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="types.prepare_class">
<code class="descclassname">types.</code><code class="descname">prepare_class</code><span class="sig-paren">(</span><em>name</em>, <em>bases=()</em>, <em>kwds=None</em><span class="sig-paren">)</span><a class="headerlink" href="#types.prepare_class" title="永久链接至目标">¶</a></dt>
<dd><p>Calculates the appropriate metaclass and creates the class namespace.</p>
<p>The arguments are the components that make up a class definition header:
the class name, the base classes (in order) and the keyword arguments
(such as <code class="docutils literal notranslate"><span class="pre">metaclass</span></code>).</p>
<p>The return value is a 3-tuple: <code class="docutils literal notranslate"><span class="pre">metaclass,</span> <span class="pre">namespace,</span> <span class="pre">kwds</span></code></p>
<p><em>metaclass</em> is the appropriate metaclass, <em>namespace</em> is the
prepared class namespace and <em>kwds</em> is an updated copy of the passed
in <em>kwds</em> argument with any <code class="docutils literal notranslate"><span class="pre">'metaclass'</span></code> entry removed. If no <em>kwds</em>
argument is passed in, this will be an empty dict.</p>
<div class="versionadded">
<p><span class="versionmodified">3.3 新版功能.</span></p>
</div>
<div class="versionchanged">
<p><span class="versionmodified">在 3.6 版更改: </span>The default value for the <code class="docutils literal notranslate"><span class="pre">namespace</span></code> element of the returned
tuple has changed.  Now an insertion-order-preserving mapping is
used when the metaclass does not have a <code class="docutils literal notranslate"><span class="pre">__prepare__</span></code> method.</p>
</div>
</dd></dl>

<div class="admonition seealso">
<p class="first admonition-title">参见</p>
<dl class="last docutils">
<dt><a class="reference internal" href="../reference/datamodel.html#metaclasses"><span class="std std-ref">元类</span></a></dt>
<dd>Full details of the class creation process supported by these functions</dd>
<dt><span class="target" id="index-6"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-3115"><strong>PEP 3115</strong></a> - Python 3000 中的元类</dt>
<dd>引入 <code class="docutils literal notranslate"><span class="pre">__prepare__</span></code> 命名空间钩子</dd>
</dl>
</div>
<dl class="function">
<dt id="types.resolve_bases">
<code class="descclassname">types.</code><code class="descname">resolve_bases</code><span class="sig-paren">(</span><em>bases</em><span class="sig-paren">)</span><a class="headerlink" href="#types.resolve_bases" title="永久链接至目标">¶</a></dt>
<dd><p>Resolve MRO entries dynamically as specified by <span class="target" id="index-1"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0560"><strong>PEP 560</strong></a>.</p>
<p>This function looks for items in <em>bases</em> that are not instances of
<a class="reference internal" href="functions.html#type" title="type"><code class="xref py py-class docutils literal notranslate"><span class="pre">type</span></code></a>, and returns a tuple where each such object that has
an <code class="docutils literal notranslate"><span class="pre">__mro_entries__</span></code> method is replaced with an unpacked result of
calling this method.  If a <em>bases</em> item is an instance of <a class="reference internal" href="functions.html#type" title="type"><code class="xref py py-class docutils literal notranslate"><span class="pre">type</span></code></a>,
or it doesn't have an <code class="docutils literal notranslate"><span class="pre">__mro_entries__</span></code> method, then it is included in
the return tuple unchanged.</p>
<div class="versionadded">
<p><span class="versionmodified">3.7 新版功能.</span></p>
</div>
</dd></dl>

<div class="admonition seealso">
<p class="first admonition-title">参见</p>
<p class="last"><span class="target" id="index-7"></span><a class="pep reference external" href="https://www.python.org/dev/peps/pep-0560"><strong>PEP 560</strong></a> - 对类型模块和泛型类型的核心支持</p>
</div>
</div>
<div class="section" id="standard-interpreter-types">
<h2>Standard Interpreter Types<a class="headerlink" href="#standard-interpreter-types" title="永久链接至标题">¶</a></h2>
<p>This module provides names for many of the types that are required to
implement a Python interpreter. It deliberately avoids including some of
the types that arise only incidentally during processing such as the
<code class="docutils literal notranslate"><span class="pre">listiterator</span></code> type.</p>
<p>Typical use of these names is for <a class="reference internal" href="functions.html#isinstance" title="isinstance"><code class="xref py py-func docutils literal notranslate"><span class="pre">isinstance()</span></code></a> or
<a class="reference internal" href="functions.html#issubclass" title="issubclass"><code class="xref py py-func docutils literal notranslate"><span class="pre">issubclass()</span></code></a> checks.</p>
<p>Standard names are defined for the following types:</p>
<dl class="data">
<dt id="types.FunctionType">
<code class="descclassname">types.</code><code class="descname">FunctionType</code><a class="headerlink" href="#types.FunctionType" title="永久链接至目标">¶</a></dt>
<dt id="types.LambdaType">
<code class="descclassname">types.</code><code class="descname">LambdaType</code><a class="headerlink" href="#types.LambdaType" title="永久链接至目标">¶</a></dt>
<dd><p>用户自定义函数以及由 <a class="reference internal" href="../reference/expressions.html#lambda"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">lambda</span></code></a>  表达式所创建函数的类型。</p>
</dd></dl>

<dl class="data">
<dt id="types.GeneratorType">
<code class="descclassname">types.</code><code class="descname">GeneratorType</code><a class="headerlink" href="#types.GeneratorType" title="永久链接至目标">¶</a></dt>
<dd><p><a class="reference internal" href="../glossary.html#term-generator"><span class="xref std std-term">generator</span></a> 迭代器对象的类型，由生成器函数创建。</p>
</dd></dl>

<dl class="data">
<dt id="types.CoroutineType">
<code class="descclassname">types.</code><code class="descname">CoroutineType</code><a class="headerlink" href="#types.CoroutineType" title="永久链接至目标">¶</a></dt>
<dd><p><a class="reference internal" href="../glossary.html#term-coroutine"><span class="xref std std-term">coroutine</span></a> 对象的类型，由 <a class="reference internal" href="../reference/compound_stmts.html#async-def"><code class="xref std std-keyword docutils literal notranslate"><span class="pre">async</span> <span class="pre">def</span></code></a> 函数创建。</p>
<div class="versionadded">
<p><span class="versionmodified">3.5 新版功能.</span></p>
</div>
</dd></dl>

<dl class="data">
<dt id="types.AsyncGeneratorType">
<code class="descclassname">types.</code><code class="descname">AsyncGeneratorType</code><a class="headerlink" href="#types.AsyncGeneratorType" title="永久链接至目标">¶</a></dt>
<dd><p><a class="reference internal" href="../glossary.html#term-asynchronous-generator"><span class="xref std std-term">asynchronous generator</span></a> 迭代器对象的类型，由异步生成器函数创建。</p>
<div class="versionadded">
<p><span class="versionmodified">3.6 新版功能.</span></p>
</div>
</dd></dl>

<dl class="data">
<dt id="types.CodeType">
<code class="descclassname">types.</code><code class="descname">CodeType</code><a class="headerlink" href="#types.CodeType" title="永久链接至目标">¶</a></dt>
<dd><p id="index-3">The type for code objects such as returned by <a class="reference internal" href="functions.html#compile" title="compile"><code class="xref py py-func docutils literal notranslate"><span class="pre">compile()</span></code></a>.</p>
</dd></dl>

<dl class="data">
<dt id="types.MethodType">
<code class="descclassname">types.</code><code class="descname">MethodType</code><a class="headerlink" href="#types.MethodType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of methods of user-defined class instances.</p>
</dd></dl>

<dl class="data">
<dt id="types.BuiltinFunctionType">
<code class="descclassname">types.</code><code class="descname">BuiltinFunctionType</code><a class="headerlink" href="#types.BuiltinFunctionType" title="永久链接至目标">¶</a></dt>
<dt id="types.BuiltinMethodType">
<code class="descclassname">types.</code><code class="descname">BuiltinMethodType</code><a class="headerlink" href="#types.BuiltinMethodType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of built-in functions like <a class="reference internal" href="functions.html#len" title="len"><code class="xref py py-func docutils literal notranslate"><span class="pre">len()</span></code></a> or <a class="reference internal" href="sys.html#sys.exit" title="sys.exit"><code class="xref py py-func docutils literal notranslate"><span class="pre">sys.exit()</span></code></a>, and
methods of built-in classes.  (Here, the term &quot;built-in&quot; means &quot;written in
C&quot;.)</p>
</dd></dl>

<dl class="data">
<dt id="types.WrapperDescriptorType">
<code class="descclassname">types.</code><code class="descname">WrapperDescriptorType</code><a class="headerlink" href="#types.WrapperDescriptorType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of methods of some built-in data types and base classes such as
<a class="reference internal" href="../reference/datamodel.html#object.__init__" title="object.__init__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">object.__init__()</span></code></a> or <a class="reference internal" href="../reference/datamodel.html#object.__lt__" title="object.__lt__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">object.__lt__()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified">3.7 新版功能.</span></p>
</div>
</dd></dl>

<dl class="data">
<dt id="types.MethodWrapperType">
<code class="descclassname">types.</code><code class="descname">MethodWrapperType</code><a class="headerlink" href="#types.MethodWrapperType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of <em>bound</em> methods of some built-in data types and base classes.
For example it is the type of <code class="code docutils literal notranslate"><span class="pre">object().__str__</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified">3.7 新版功能.</span></p>
</div>
</dd></dl>

<dl class="data">
<dt id="types.MethodDescriptorType">
<code class="descclassname">types.</code><code class="descname">MethodDescriptorType</code><a class="headerlink" href="#types.MethodDescriptorType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of methods of some built-in data types such as <a class="reference internal" href="stdtypes.html#str.join" title="str.join"><code class="xref py py-meth docutils literal notranslate"><span class="pre">str.join()</span></code></a>.</p>
<div class="versionadded">
<p><span class="versionmodified">3.7 新版功能.</span></p>
</div>
</dd></dl>

<dl class="data">
<dt id="types.ClassMethodDescriptorType">
<code class="descclassname">types.</code><code class="descname">ClassMethodDescriptorType</code><a class="headerlink" href="#types.ClassMethodDescriptorType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of <em>unbound</em> class methods of some built-in data types such as
<code class="docutils literal notranslate"><span class="pre">dict.__dict__['fromkeys']</span></code>.</p>
<div class="versionadded">
<p><span class="versionmodified">3.7 新版功能.</span></p>
</div>
</dd></dl>

<dl class="class">
<dt id="types.ModuleType">
<em class="property">class </em><code class="descclassname">types.</code><code class="descname">ModuleType</code><span class="sig-paren">(</span><em>name</em>, <em>doc=None</em><span class="sig-paren">)</span><a class="headerlink" href="#types.ModuleType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of <a class="reference internal" href="../glossary.html#term-module"><span class="xref std std-term">modules</span></a>. Constructor takes the name of the
module to be created and optionally its <a class="reference internal" href="../glossary.html#term-docstring"><span class="xref std std-term">docstring</span></a>.</p>
<div class="admonition note">
<p class="first admonition-title">注解</p>
<p class="last">Use <a class="reference internal" href="importlib.html#importlib.util.module_from_spec" title="importlib.util.module_from_spec"><code class="xref py py-func docutils literal notranslate"><span class="pre">importlib.util.module_from_spec()</span></code></a> to create a new module if you
wish to set the various import-controlled attributes.</p>
</div>
<dl class="attribute">
<dt id="types.ModuleType.__doc__">
<code class="descname">__doc__</code><a class="headerlink" href="#types.ModuleType.__doc__" title="永久链接至目标">¶</a></dt>
<dd><p>The <a class="reference internal" href="../glossary.html#term-docstring"><span class="xref std std-term">docstring</span></a> of the module. Defaults to <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
</dd></dl>

<dl class="attribute">
<dt id="types.ModuleType.__loader__">
<code class="descname">__loader__</code><a class="headerlink" href="#types.ModuleType.__loader__" title="永久链接至目标">¶</a></dt>
<dd><p>The <a class="reference internal" href="../glossary.html#term-loader"><span class="xref std std-term">loader</span></a> which loaded the module. Defaults to <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
<div class="versionchanged">
<p><span class="versionmodified">在 3.4 版更改: </span>Defaults to <code class="docutils literal notranslate"><span class="pre">None</span></code>. Previously the attribute was optional.</p>
</div>
</dd></dl>

<dl class="attribute">
<dt id="types.ModuleType.__name__">
<code class="descname">__name__</code><a class="headerlink" href="#types.ModuleType.__name__" title="永久链接至目标">¶</a></dt>
<dd><p>The name of the module.</p>
</dd></dl>

<dl class="attribute">
<dt id="types.ModuleType.__package__">
<code class="descname">__package__</code><a class="headerlink" href="#types.ModuleType.__package__" title="永久链接至目标">¶</a></dt>
<dd><p>Which <a class="reference internal" href="../glossary.html#term-package"><span class="xref std std-term">package</span></a> a module belongs to. If the module is top-level
(i.e. not a part of any specific package) then the attribute should be set
to <code class="docutils literal notranslate"><span class="pre">''</span></code>, else it should be set to the name of the package (which can be
<a class="reference internal" href="../reference/import.html#__name__" title="__name__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__name__</span></code></a> if the module is a package itself). Defaults to <code class="docutils literal notranslate"><span class="pre">None</span></code>.</p>
<div class="versionchanged">
<p><span class="versionmodified">在 3.4 版更改: </span>Defaults to <code class="docutils literal notranslate"><span class="pre">None</span></code>. Previously the attribute was optional.</p>
</div>
</dd></dl>

</dd></dl>

<dl class="class">
<dt id="types.TracebackType">
<em class="property">class </em><code class="descclassname">types.</code><code class="descname">TracebackType</code><span class="sig-paren">(</span><em>tb_next</em>, <em>tb_frame</em>, <em>tb_lasti</em>, <em>tb_lineno</em><span class="sig-paren">)</span><a class="headerlink" href="#types.TracebackType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of traceback objects such as found in <code class="docutils literal notranslate"><span class="pre">sys.exc_info()[2]</span></code>.</p>
<p>See <a class="reference internal" href="../reference/datamodel.html#traceback-objects"><span class="std std-ref">the language reference</span></a> for details of the
available attributes and operations, and guidance on creating tracebacks
dynamically.</p>
</dd></dl>

<dl class="data">
<dt id="types.FrameType">
<code class="descclassname">types.</code><code class="descname">FrameType</code><a class="headerlink" href="#types.FrameType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of frame objects such as found in <code class="docutils literal notranslate"><span class="pre">tb.tb_frame</span></code> if <code class="docutils literal notranslate"><span class="pre">tb</span></code> is a
traceback object.</p>
<p>See <a class="reference internal" href="../reference/datamodel.html#frame-objects"><span class="std std-ref">the language reference</span></a> for details of the
available attributes and operations.</p>
</dd></dl>

<dl class="data">
<dt id="types.GetSetDescriptorType">
<code class="descclassname">types.</code><code class="descname">GetSetDescriptorType</code><a class="headerlink" href="#types.GetSetDescriptorType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of objects defined in extension modules with <code class="docutils literal notranslate"><span class="pre">PyGetSetDef</span></code>, such
as <code class="docutils literal notranslate"><span class="pre">FrameType.f_locals</span></code> or <code class="docutils literal notranslate"><span class="pre">array.array.typecode</span></code>.  This type is used as
descriptor for object attributes; it has the same purpose as the
<a class="reference internal" href="functions.html#property" title="property"><code class="xref py py-class docutils literal notranslate"><span class="pre">property</span></code></a> type, but for classes defined in extension modules.</p>
</dd></dl>

<dl class="data">
<dt id="types.MemberDescriptorType">
<code class="descclassname">types.</code><code class="descname">MemberDescriptorType</code><a class="headerlink" href="#types.MemberDescriptorType" title="永久链接至目标">¶</a></dt>
<dd><p>The type of objects defined in extension modules with <code class="docutils literal notranslate"><span class="pre">PyMemberDef</span></code>, such
as <code class="docutils literal notranslate"><span class="pre">datetime.timedelta.days</span></code>.  This type is used as descriptor for simple C
data members which use standard conversion functions; it has the same purpose
as the <a class="reference internal" href="functions.html#property" title="property"><code class="xref py py-class docutils literal notranslate"><span class="pre">property</span></code></a> type, but for classes defined in extension modules.</p>
<div class="impl-detail compound">
<p><strong>CPython implementation detail:</strong> In other implementations of Python, this type may be identical to
<code class="docutils literal notranslate"><span class="pre">GetSetDescriptorType</span></code>.</p>
</div>
</dd></dl>

<dl class="class">
<dt id="types.MappingProxyType">
<em class="property">class </em><code class="descclassname">types.</code><code class="descname">MappingProxyType</code><span class="sig-paren">(</span><em>mapping</em><span class="sig-paren">)</span><a class="headerlink" href="#types.MappingProxyType" title="永久链接至目标">¶</a></dt>
<dd><p>Read-only proxy of a mapping. It provides a dynamic view on the mapping's
entries, which means that when the mapping changes, the view reflects these
changes.</p>
<div class="versionadded">
<p><span class="versionmodified">3.3 新版功能.</span></p>
</div>
<dl class="describe">
<dt>
<code class="descname">key in proxy</code></dt>
<dd><p>Return <code class="docutils literal notranslate"><span class="pre">True</span></code> if the underlying mapping has a key <em>key</em>, else
<code class="docutils literal notranslate"><span class="pre">False</span></code>.</p>
</dd></dl>

<dl class="describe">
<dt>
<code class="descname">proxy[key]</code></dt>
<dd><p>Return the item of the underlying mapping with key <em>key</em>.  Raises a
<a class="reference internal" href="exceptions.html#KeyError" title="KeyError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyError</span></code></a> if <em>key</em> is not in the underlying mapping.</p>
</dd></dl>

<dl class="describe">
<dt>
<code class="descname">iter(proxy)</code></dt>
<dd><p>Return an iterator over the keys of the underlying mapping.  This is a
shortcut for <code class="docutils literal notranslate"><span class="pre">iter(proxy.keys())</span></code>.</p>
</dd></dl>

<dl class="describe">
<dt>
<code class="descname">len(proxy)</code></dt>
<dd><p>Return the number of items in the underlying mapping.</p>
</dd></dl>

<dl class="method">
<dt id="types.MappingProxyType.copy">
<code class="descname">copy</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#types.MappingProxyType.copy" title="永久链接至目标">¶</a></dt>
<dd><p>Return a shallow copy of the underlying mapping.</p>
</dd></dl>

<dl class="method">
<dt id="types.MappingProxyType.get">
<code class="descname">get</code><span class="sig-paren">(</span><em>key</em><span class="optional">[</span>, <em>default</em><span class="optional">]</span><span class="sig-paren">)</span><a class="headerlink" href="#types.MappingProxyType.get" title="永久链接至目标">¶</a></dt>
<dd><p>Return the value for <em>key</em> if <em>key</em> is in the underlying mapping, else
<em>default</em>.  If <em>default</em> is not given, it defaults to <code class="docutils literal notranslate"><span class="pre">None</span></code>, so that
this method never raises a <a class="reference internal" href="exceptions.html#KeyError" title="KeyError"><code class="xref py py-exc docutils literal notranslate"><span class="pre">KeyError</span></code></a>.</p>
</dd></dl>

<dl class="method">
<dt id="types.MappingProxyType.items">
<code class="descname">items</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#types.MappingProxyType.items" title="永久链接至目标">¶</a></dt>
<dd><p>Return a new view of the underlying mapping's items (<code class="docutils literal notranslate"><span class="pre">(key,</span> <span class="pre">value)</span></code>
pairs).</p>
</dd></dl>

<dl class="method">
<dt id="types.MappingProxyType.keys">
<code class="descname">keys</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#types.MappingProxyType.keys" title="永久链接至目标">¶</a></dt>
<dd><p>Return a new view of the underlying mapping's keys.</p>
</dd></dl>

<dl class="method">
<dt id="types.MappingProxyType.values">
<code class="descname">values</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#types.MappingProxyType.values" title="永久链接至目标">¶</a></dt>
<dd><p>Return a new view of the underlying mapping's values.</p>
</dd></dl>

</dd></dl>

</div>
<div class="section" id="additional-utility-classes-and-functions">
<h2>Additional Utility Classes and Functions<a class="headerlink" href="#additional-utility-classes-and-functions" title="永久链接至标题">¶</a></h2>
<dl class="class">
<dt id="types.SimpleNamespace">
<em class="property">class </em><code class="descclassname">types.</code><code class="descname">SimpleNamespace</code><a class="headerlink" href="#types.SimpleNamespace" title="永久链接至目标">¶</a></dt>
<dd><p>A simple <a class="reference internal" href="functions.html#object" title="object"><code class="xref py py-class docutils literal notranslate"><span class="pre">object</span></code></a> subclass that provides attribute access to its
namespace, as well as a meaningful repr.</p>
<p>Unlike <a class="reference internal" href="functions.html#object" title="object"><code class="xref py py-class docutils literal notranslate"><span class="pre">object</span></code></a>, with <code class="docutils literal notranslate"><span class="pre">SimpleNamespace</span></code> you can add and remove
attributes.  If a <code class="docutils literal notranslate"><span class="pre">SimpleNamespace</span></code> object is initialized with keyword
arguments, those are directly added to the underlying namespace.</p>
<p>The type is roughly equivalent to the following code:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="k">class</span> <span class="nc">SimpleNamespace</span><span class="p">:</span>
    <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="vm">__dict__</span><span class="o">.</span><span class="n">update</span><span class="p">(</span><span class="n">kwargs</span><span class="p">)</span>

    <span class="k">def</span> <span class="nf">__repr__</span><span class="p">(</span><span class="bp">self</span><span class="p">):</span>
        <span class="n">keys</span> <span class="o">=</span> <span class="nb">sorted</span><span class="p">(</span><span class="bp">self</span><span class="o">.</span><span class="vm">__dict__</span><span class="p">)</span>
        <span class="n">items</span> <span class="o">=</span> <span class="p">(</span><span class="s2">&quot;</span><span class="si">{}</span><span class="s2">=</span><span class="si">{!r}</span><span class="s2">&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="n">k</span><span class="p">,</span> <span class="bp">self</span><span class="o">.</span><span class="vm">__dict__</span><span class="p">[</span><span class="n">k</span><span class="p">])</span> <span class="k">for</span> <span class="n">k</span> <span class="ow">in</span> <span class="n">keys</span><span class="p">)</span>
        <span class="k">return</span> <span class="s2">&quot;</span><span class="si">{}</span><span class="s2">(</span><span class="si">{}</span><span class="s2">)&quot;</span><span class="o">.</span><span class="n">format</span><span class="p">(</span><span class="nb">type</span><span class="p">(</span><span class="bp">self</span><span class="p">)</span><span class="o">.</span><span class="vm">__name__</span><span class="p">,</span> <span class="s2">&quot;, &quot;</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">items</span><span class="p">))</span>

    <span class="k">def</span> <span class="nf">__eq__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">other</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="vm">__dict__</span> <span class="o">==</span> <span class="n">other</span><span class="o">.</span><span class="vm">__dict__</span>
</pre></div>
</div>
<p><code class="docutils literal notranslate"><span class="pre">SimpleNamespace</span></code> may be useful as a replacement for <code class="docutils literal notranslate"><span class="pre">class</span> <span class="pre">NS:</span> <span class="pre">pass</span></code>.
However, for a structured record type use <a class="reference internal" href="collections.html#collections.namedtuple" title="collections.namedtuple"><code class="xref py py-func docutils literal notranslate"><span class="pre">namedtuple()</span></code></a>
instead.</p>
<div class="versionadded">
<p><span class="versionmodified">3.3 新版功能.</span></p>
</div>
</dd></dl>

<dl class="function">
<dt id="types.DynamicClassAttribute">
<code class="descclassname">types.</code><code class="descname">DynamicClassAttribute</code><span class="sig-paren">(</span><em>fget=None</em>, <em>fset=None</em>, <em>fdel=None</em>, <em>doc=None</em><span class="sig-paren">)</span><a class="headerlink" href="#types.DynamicClassAttribute" title="永久链接至目标">¶</a></dt>
<dd><p>Route attribute access on a class to __getattr__.</p>
<p>This is a descriptor, used to define attributes that act differently when
accessed through an instance and through a class.  Instance access remains
normal, but access to an attribute through a class will be routed to the
class's __getattr__ method; this is done by raising AttributeError.</p>
<p>This allows one to have properties active on an instance, and have virtual
attributes on the class with the same name (see Enum for an example).</p>
<div class="versionadded">
<p><span class="versionmodified">3.4 新版功能.</span></p>
</div>
</dd></dl>

</div>
<div class="section" id="coroutine-utility-functions">
<h2>Coroutine Utility Functions<a class="headerlink" href="#coroutine-utility-functions" title="永久链接至标题">¶</a></h2>
<dl class="function">
<dt id="types.coroutine">
<code class="descclassname">types.</code><code class="descname">coroutine</code><span class="sig-paren">(</span><em>gen_func</em><span class="sig-paren">)</span><a class="headerlink" href="#types.coroutine" title="永久链接至目标">¶</a></dt>
<dd><p>This function transforms a <a class="reference internal" href="../glossary.html#term-generator"><span class="xref std std-term">generator</span></a> function into a
<a class="reference internal" href="../glossary.html#term-coroutine-function"><span class="xref std std-term">coroutine function</span></a> which returns a generator-based coroutine.
The generator-based coroutine is still a <a class="reference internal" href="../glossary.html#term-generator-iterator"><span class="xref std std-term">generator iterator</span></a>,
but is also considered to be a <a class="reference internal" href="../glossary.html#term-coroutine"><span class="xref std std-term">coroutine</span></a> object and is
<a class="reference internal" href="../glossary.html#term-awaitable"><span class="xref std std-term">awaitable</span></a>.  However, it may not necessarily implement
the <a class="reference internal" href="../reference/datamodel.html#object.__await__" title="object.__await__"><code class="xref py py-meth docutils literal notranslate"><span class="pre">__await__()</span></code></a> method.</p>
<p>If <em>gen_func</em> is a generator function, it will be modified in-place.</p>
<p>If <em>gen_func</em> is not a generator function, it will be wrapped. If it
returns an instance of <a class="reference internal" href="collections.abc.html#collections.abc.Generator" title="collections.abc.Generator"><code class="xref py py-class docutils literal notranslate"><span class="pre">collections.abc.Generator</span></code></a>, the instance
will be wrapped in an <em>awaitable</em> proxy object.  All other types
of objects will be returned as is.</p>
<div class="versionadded">
<p><span class="versionmodified">3.5 新版功能.</span></p>
</div>
</dd></dl>

</div>
</div>


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  <h3><a href="../contents.html">Table of Contents</a></h3>
  <ul>
<li><a class="reference internal" href="#"><code class="docutils literal notranslate"><span class="pre">types</span></code> --- Dynamic type creation and names for built-in types</a><ul>
<li><a class="reference internal" href="#dynamic-type-creation">Dynamic Type Creation</a></li>
<li><a class="reference internal" href="#standard-interpreter-types">Standard Interpreter Types</a></li>
<li><a class="reference internal" href="#additional-utility-classes-and-functions">Additional Utility Classes and Functions</a></li>
<li><a class="reference internal" href="#coroutine-utility-functions">Coroutine Utility Functions</a></li>
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